Latitude-longitude counter



J y 29, 1952 E. NYYSSONEN EI'AL 2,605,047

LATITUDE LONGITUDE COUNTER Filed Maroh 14, 1946 3 Sheets-Sheet lINVENTORS EINARD NYYSSONEN ARTHUR c. HUGHES, .JR.

ATTORNEY y 9, 1952 E. NYYSSONEN ETTAL LATITUDE LONGITUDE COUNTER 3Sheets-Sheet Tiled March 14, 1946 [NVENTORS E INARD NYYSSONEN ART UR BYH C HUGHES, JR

ATTORNEY Patented July 29, 1952 LATITUDE-LONGITUDE COUNTER EinardNyyssonen, Watertown, Mass, and Arthur C. Hughes, Jr., Puente, Calif.,assignors, by mesne assignments, to the United States of America asrepresented by the Secretary of the Navy Application March 14, 1946,Serial No. 654,495

5 Claims.

This invention relates to automatic counting mechanisms, and moreparticularly to latitudelongitude counters featuring a novel automaticscreening shutter to prevent gross errors in reading.

The prior art has included cumulative coun ing mechanisms (though noneadapted to latitude-longitude counting). In such counting mechanisms,however, a difficulty has existed because of the necessity of countingin either direction from a zero reference point. This requires twocounters of opposite hand on a single counting shaft. As one counterreads increasing from zero the other runs backward from zero, thusgiving a reading completely meaningless. This invention incorporates ashutter which conceals the meaningless reading at all times.

A general object of this invention is to provide an automatic countingmechanism for compiling and presenting data on the changing latitude orlongitude of the unit upon which said counting mechanism is mounted.

Another object of this invention is to provide an automatic countingmechanism having means disposed therein for eliminating the ambiguity ofpresentation heretofore disadvantageous in the art.

A further object of this invention is to provide an automatic countingmechanism comprising a shutter, said shutter acting to screen at alltimes whichever of the two readings on the counter is meaningless.

Still another object of this invention is to provide a longitude orlatitude counter, said counter comprising a shutter which will screenthe west (or south) reading when the true reading is east (or north),and vice versa.

Further objects and advantages of this invention will be apparent fromthe following description and claims, taken in connection with theaccompanying drawings, in which:

Fig. 1 is a perspective view of a simplified device illustrating, inprinciple only, the shutteroperating mechanism of this invention;

Fig. 2 is a perspective view of a modified, nonstandard, transfer pinionas used in the shutteroperating mechanism of this invention;

Figs. 3, 4, 5, and 6 are detailed assembly views of the entire countingmechanism, including shutter.

Referring to Fig. 1 there is shown a schematic representation of theshutter-operating mechanism of this invention. It should be emphasizedthat Fig. 1 is schematic only, and is presented to illustrate principle.In detail it differs from the shutter-operating mechanism as actuallyconstructed. In Fig. 1 there is shown a shutter H), pivotally mounted ona rotatable driven shaft I2. Shaft |2 drives two transfer step-toothgears l3 and I4, and two locking gears |5 and I6. These four gears aredriven from shaft |2 in the same direction of rotation as shaft |2itself travels, but they advance only intermittently as the shaftrotates steadily. The gearing between shaft I2 and gears |3, |4, l5, andI6 is not shown in Fig. l, but appears in Figs. 4 and 5. Gears l3 and I5of Fig. 1 correspond to gears of the west motion in the actual device,and gears l4 and I5 represent gears of the east motion. (See Figs. 3, 4,and 5). Gears l1 and I8, fixedly secured to a camshaft 2|, representtransfer pinion and locking teeth, respectively, for the west counter.Gears I9 and 20 perform similarly for the east counter. Transferstep-tooth gears l3 and M are provided with airs of teeth 22 and 23,respectively, for imparting motion to pinions I1 and I9. Locking gearsl5 and I6 have mating tooth spaces 24 and 25, respectively, to receivelocking teeth l8 and 20. A cam 26, fixedly mounted on camshaft 2|, isprovided with a pin 21. Pin 2'! engages a slot 28 in shutter l0, therebyimparting rotation about shaft |2 to shutter 0, in response to rotationof camshaft 2|.

Referring to Fig. 2, there is shown a preferred form of construction ofone of the two similar transfer pinions and I9 having one of the twosimilar locking teeth I8 and 20 formed integral therewith. Thesetransfer pinions differ from a standard transfer locking pinion in thatonly two locking teeth are present on each pinion. A standardeight-tooth locking pinion has four locking teeth, made by eliminatingalternate teeth from part of the gear thickness. The two non-standardtransfer locking pinions of this shutter-operating mechanism are fixedlyso mounted on camshaft 2| as to have the axes of locking teeth mutuallyperpendicular.

With the counter at zero reading, the relative position of transferstep-tooth gears, locking gears and transfer locking pinions is as shownin Fig. 1. Note that pairs of transfer gear teeth 22 and 23 straddlecamshaft 2|, and that camshaft 2| is locked in position by locking teethl8 and 20 bearing respectively on the peripheries of locking gears l5and I6. With camshaft 2| in this position, pin 21 is at its uppermostposition, and therefore shutter I0 is held in the neutral (zero)position. (In the actual device both zero readings are then visible,neither covered by the shutter.) Assume then that shaft I2 is turnedclockwise as seen from the driven (right-hand, in Fig. 1) end. Thisclockwise motion is associated with eastward travel. Teeth of gears 14and I6 move away from their opposing teeth and have no effect. Teeth ofgears l3 and I5, however, mesh with I! and is thereby causing atwo-tooth -revolution) advance of gear ll. This motion is imparted topin 21 as a 90-degree rotation about camshaft 2 I, which rotation isenough to move the shutter from its zero position to one which screensthe (west) opening associated with gears 13 and IE but leaves revealedthe (east) opening associated with gears l4 and 16. With continuedeastward travel camshaft 2! will be locked in the above-defined positionuntil, at 180 longitude, teeth 23 and 25 impart another A;,-revolutionto camshaft 2! through gears 19 and 20. The resulting effect is toreturn the shutter to its original (zero) position. It should be notedthat the shutter is locked in position by locking teeth [8 and 20, andthe shutter can move only when tooth 18 or 20 engages mating tooth space24 or 25 of locking gear [5 or IS.

The preceding description of operation deals only with the gears whichfinally move the shutter. The mechanism constitutes only a part of thisinvention, the remaining essential features of which may be described asfollows.

Referring to Fig. 3, a top exterior view of the counter, there is shownthe numbering system on the four wheels from which longitude is read.(The four wheels for east longitude will be considered, it being kept inmind that the four for west longitude are numbered similarly but ofopposite hand.) Wheel 30 is keyed to shaft l2 which, rotates once totwo'turns of an input shaft 35. As input shaft 35 turns one revolutionper l0 of longitude, wheel 30 turns one revolution per 020 of longitude.Wheel 30 is graduated in single minutes with the numbers running from 0to 9 twice on the circumference. In the following discussion the termtransfer is taken to signify means whereby one wheel after rotating apredetermined amount causes a'second wheel to advance one rotationalstep of predetermined size. Wheel 30' has two transfers to advance wheel3|, graduated in tens of minutes, with the values running from 0 to 50thrice. Wheel 3! has three transfers to advance wheel 32, graduated insingle degrees with the figures running from 0 to 9 twice, as on wheel30. Wheel 32 has two transfers to advance a tensof-degrees wheel 33,graduated from 0 to 18, representing 0' to 180, once in itscircumference. Wheel 33 has one transfer to effect the shutter operationalready described. All transfers up to but not including the actuatingof camshaft 2| are accomplished with standard eight-tooth transferlocking pinions, heretofore described in connection with Fig. 2. Asheretofore stated, actuating of camshaft 2| is accomplished throughnon-standard transfer locking pinions each having only two lockingteeth.

Referring to Fig. 4, there is shown a sectional elevation of theassembly. This figure, with Figs. and 6, shows the actual layout andposition of camshaft 21, shown only schematically in Fig. 1. Figs. 5 and6 show also the arrangement of the standardtransferpinions. I v

Consider a transfer operation commencing from longitude zero, at whichpoint a zero reading is visible on both east and west scales. Assumetravelis eastward. When the west counter turns (backward) to 1 7959',the associated transfer gear will rotate 20 degrees (on thetens-of-degrees wheel, one-eighteenth of one revolution). Because of theinitial position of transfer step-tooth gear [3, the first half of this20-degree rotation merely brings the first of the pair of transfer teeth22 to bear on transfer pinion H. The remaining ill-degree rotation willadvance transfer pinion H by one tooth. With eight teeth in the pinion,this will necessarily rotate the camshaft 45 degrees, enough to closethe shutter over the aperture for west readings. Fig. l is helpful inunderstanding this action.

With continued eastward travel the West transfer gear advances againwhen the west reading (already hidden by the shutter) drops from to16959. At this time transfer gear 13 turns another twenty degrees. Ofthis, the first ten degrees rotates the camshaft 45 degrees and thefinal ten degrees moves the transfer step teeth 22 away from the pinion,thus providing working clearance. It will be observed that this second45 degree rotation of camshaft 21 moves shutter 10 only a small andunessential amount.

With subsequent travel from east to west the driven shaft l2 wouldrevolve in the reverse direction (counterclockwise as seen from thedriven end). As longitude changed from east to west, shutter H) wouldscreen the east reading and reveal the west.

A longitude counter has been described. A latitude counter would dilferin that readings would be north and south rather than east and west.Also, wheels reading tens of degrees would be graduated from 0 to 9 (0)twice in their periphery, rather than from 0 to 18 (0) once.

What is claimed is:

1. An indicating mechanism comprising a plurality of numeral wheels eachbearing a set of numerals and arranged in two groups of wheels, thenumerals on the wheels of one group progressively increasing in anopposite direction to the numerals of the other group, an actuatingshaft, an intermediate transfer drive connection between said wheels, ashutter pivotally mounted on said shaft for selectively screening one orthe other of said groups of wheels, a second shaft mounted in parallelrelationship with said first shaft, a geared connection between saidtransfer drive and said second shaft to rotate said second shaft apredetermined amount, a disc crank connection between said second shaftand said shutter to position said shutter, and locked gearing to preventrotation of said shutter other than by said transfer drive.

2. An indicating mechanism comprising an actuating shaft, a plurality ofnumeral wheels mounted in axial alignment on said shaft each bearingthereon a set of numerals and arranged in two groups of wheels, thenumerals on the wheels of one group progressively increasing in anopposite direction to the numerals of the other group for the samedirection of rotation of said wheels, an intermediate transfer driveconnection between said wheels in each group, a shutter pivotallymounted on said shaft, a second shaft mounted in parallel relationshipwith said first shaft, a gear connection between said transfer drive andsaid second shaft to rotate said second shaft a predetermined amount, adisc crank connection between said second shaft and said shutter torotate said shutter a predetermined amount about said first shaft uponrotation of said second shaft thereby selectively screening one or theotherbf said groups of numeral wheels, and locked gearing to preventrotation of said second shaft other than .by said transfer drive.

3. An indicating mechanism comprising, a plurality of counter wheelseach bearing a set of. indicia and arranged in two groups of wheels, the

indicia on the wheels of one group progressively increasing in anopposite sense to the indicia of the other group, a normally lockedshutter for screening one or the other of said groups, and meansoperable in response to the rotation of said wheels for automaticallyunlocking said shutter, causing said shutter to shift its screeningposition and relocking said shutter.

4. An indicating mechanism comprising, a

shaft, a plurality of numeral wheels each bearing a set of numerals andmounted on said shaft in two groups. the numerals on the wheels of onegroup progressively increasing in an opp site direction to the numeralsof the other group, means for periodically causing rotation of saidwheels in response to rotation of said shaft, a shutter pivotallymounted on said shaft, a second shaft mechanically coupled to saidshutter, means I shaft in two groups, the numerals of the wheels of onegroup progressively increasing in an opposite direction to the numeralsof the other group, means operable in response to rotation of said shaftfor periodically rotating said wheels a predetermined amount, a shutterpivotally mounted on said shaft, a second shaft disposed in parallelrelationship with respect to said first shaft, locking means forpreventing rotation of said second shaft, means for rotating saidshutter a predetermlned amount about said first shaft in response torotation of said second shaft to screen one or the other of said groups,and means for unlocking said second shaft causing said second shaft tomove said shutter from one screening position to the other and relockingsaid second shaft in response to periodic rotation of said numeralwheels.

EINARD NYYSSONE'N. ARTHUR C. HUGHES, JR.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,542,465 Macgill June 16, 19252,260,541 Schivenn Oct. 28, 1941 2,310,347 Ber-ck Feb. 9, 1943 FOREIGNPATENTS Number Country Date 29,422 Great Britain 1904

